HOLD OFF on R6 Firmware update!
I don;t mean to be alarmist, but the 1.3 update has been taken down from most Canon sites. It's not coordinated, so it may still be out there on some servers. Asia had it down some time before USA for example.
Without knowing why it's been taken down, I'd advise on the side of caution and NOT do the update if you have not yet.
Many thanks for drawing attention to this! I always follow the "wait and see" approach to firmware updates anyway, but this sudden pulling of the update doesn't inspire confidence.